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4" STATION + OIL

0 OIL & PUMICE if. PLASTICS ® PLASTICS & PUMICE © PUMICE

^ ANTARCTIC FRONT

Neuston tow stations off southern New Zealand and across the Southern Ocean into the Ross Sea from which pelagic plastics, tarry residues and pumice granules have been recovered. A slight concentration of plastics and pumice at the Polar Front is evident : a single plastic granule was taken at a station south of the Front (data for the austral summers of 1980, 1981/82, 1982/83 and 1985 : sources Gregory et al., 1984b; Gregory, 1987).

Fig. 11.6. Lumber thrown up on the beach at Foyn Island in the Possession Group, northern Ross Sea. Size and shape of some pieces suggest that they come from disintegrating discarded cargo pallets with a source at the abandoned Hallet Station over 50 km to the south.

spreads northwards along the coast (Gregory et al., 1984b). A further source of litter pollution exists in domestic garbage and trash dumped haphazardly overboard in the traditional seafarer manner (Fig. 11.7), since vessels operating in this region seldom have onboard incineration or other disposal facilities.

Gregory et al. (1984b) suggested that pollutants from these sources spread northwards along the coast (see Fig. 11.11) driven by the strong clockwise gyral circulation of the western Ross Sea, which effectively isolates this pelagic litter system from any exchange with material trapped at the Polar Front to the north.

Fig. 11.7. Ships's garbage afloat on a tranquil Ross Sea.

An encrusting biota, of the kind common in middle and low latitudes (Winstone, 1982; Gregory, 1983), has not so far been observed on metal, wood, plastic and other items of the litter stranding around the Ross Sea (Gregory et al., 1984b).

Gregory et al. (1984b) expressed the opinion that, while the minor quantities of pollutants stranding on these high latitude shores are aesthetically distasteful, they are not of any great environmental consequence at present. On the other hand, and although not a marine pollution matter in the strict sense, it should be noted that Johnston (1971) has recorded the death of skuas (Catharacta mac-cormicki) at Cape Hallett through crop rupture following ingestion of corn cobs.

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